George Clooney is rumoured to be gearing up to marry Brad Pitt and Angelina Jolie.

The power couple got engaged in April 2012 after seven years together, but are yet to set a date for their big day. There has been constant speculation about when they will tie the knot, and it's now been reported that Pitt's good friend Clooney will have a large part in the ceremony.

"It was Brad's idea to have George involved but he was shocked when he actually agreed," an insider told British newspaper The Daily Star."Now he's started calling him the Reverend George Clooney. He is taking it all very seriously and has already had discussions about what kind of service they'd like."

It's claimed Clooney, 52, has already been online to obtain a license allowing him to officiate weddings.

He will apparently do the honours when Pitt and Jolie exchange vows this summer, reportedly in one of several ceremonies they have planned.

"George has made it clear he's dead against marriage for himself but he can't wait to help his friends tie the knot. Neither Brad nor Ange are particularly religious but are very spiritual and want the service at their home to feel traditional," the insider added.

Pitt and Jolie decided against marrying straight after their engagement as they wanted to wait until gay couples were allowed to wed in the US.

Clooney has tied the knot once, but he and Talia Balsam divorced in 1993. Since then he has been linked to a string of beautiful women, with his most recent relationship with Stacy Keibler ending last year.

Recently there has been speculation about his relationship with British lawyer Amal Alamuddin, who accompanied him to the White House for a screening of his latest movie The Monuments Men. They have been seen out at a bar too, but he has insisted there is no romance between them.